We’re often told that dialogue should stay on topic, and that’s because dialogue is seen primarily as a means of imparting information. But there’s more to these exchanges. Take the example below. It’s typical of a conversation between characters in many TV series:
A: “So what have we got on John Smith?”
B: “He graduated from the Naval Academy in ’98, married a CIA agent in ’03. She had an affair in ’06 and John Smith found out about it.
C: “Yeah, and it turns out her lover was Jack Jones, Smith’s lieutenant. Smith ended up punching Jones’ lights out and ended up in the brig.”
B: “One incident led to another, and Smith was finally court-martialed and dismissed from the service.
A: “So now we have one more suspect who could have planted the drugs on Jones.”
C: “Right, Boss.”
A: “Let’s pay Mr. Smith a visit.”
A great deal of information passes between the characters, which is a good way of using dialogue to avoid a narrative information dump. But this conversation also helps “A” toward his goal of questioning everyone close to the lieutenant who may have had reason to frame him.
So, as you begin putting words in your characters’ mouths consider what the protagonist’s goal is. Provide the information he needs to draw conclusions that move the plot along.
Often, dialogue that wanders away from the topic gives us insight as to what makes characters tick: their moods, attitudes, values, etc. And it can layer over a subtext that’s never spoken aloud.
One of the best examples that comes to my mind is Hemingway’s “Hills Like White Elephants.” For those who haven’t read it-do! But the mini version is this: A man and woman are waiting at a railroad station, for the train from Barcelona to Madrid. While having drinks to pass the time, the man tries to convince the woman to do something she’s reluctant to. What is never mentioned is what sparked the seemingly idle conversation: she is pregnant and he wants her to have an abortion.
Now you have one more reason to take up watercolors or basket weaving instead of writing!